In certain downhole operations, power is needed to run various components of a downhole assembly. For example, power is needed to drive actuators for valves and other components, and to power various sensors and communication devices. In many cases, power is generated downhole via a downhole power generation device that is coupled to the downhole assembly. Some of the devices may be designed to use mechanical power from the fluid flow to generate electric power downhole such as the mechanisms using flow induced vibration. For example, piezoelectric elements have been used in such devices to generate electric energy when actuated by the fluid flow. The current state of the art is to expose small and independent piezoelectric elements to the main flow stream, which causes the piezoelectric elements to vibrate and generate electricity. Typically, the flow stream induces a relatively high frequency of vibration, such as 1 kHz or higher. However, such flow streams are likely to carry particulates and debris. Thus, when the piezoelectric elements are directly exposed to the particle-laden flow stream, the piezoelectric elements are likely to experience increased fatigue and erosion caused by the particulates. Additionally, the high vibrational frequency induced by the flow stream further adds to the fatigue experienced by the piezoelectric elements These factors translate into a shortened operational life of the power generation system.